1. Field of the Invention
The present invention relates generally to storage and retrieval of files, and more particularly to the storage and retrieval of indexed files corresponding to documents.
2. Discussion of the Related Art
Conventional document filing systems include some sort of memory for storing documents which have been scanned, as well as some capability to retrieve the files from memory. A technique for file storage disclosed in Japanese Patent Laid Open No. 294587-1986 compiles a file by first condensing picture image information from a document before storage into memory in order to reduce the amount of memory necessary for storing the document. The file may be later retrieved by providing identifying information via a keyboard and using the retrieved information to display the corresponding picture image on a CRT.
Retrieving a file by providing identifying information via a keyboard makes it difficult to associate the desired picture images with the identifying information accurately. This in turn delays the presentation of the desired display on the CRT. An additional disadvantage of this technique is the complicated operations which are required to retrieve files, and the large size of the equipment necessary to accommodate a CRT display unit.
Another technique for file retrieval is disclosed in the Japanese Patent Laid Open No. 61864-1989. This technique uses a system with an input-output panel having a liquid crystal display portion combined with an input tablet. Reduced-scale picture images corresponding to the individual files are displayed on the liquid crystal display portion, and files are retrieved by selecting a desired reduced-scale picture image with some type of pen.
This second technique is expensive, however, because the input-output panel must be specially constructed by superposition of a liquid crystal display portion onto an input tablet. This technique can be even more expensive if the input-output panel is enlarged because the liquid crystal display portion would occupy a larger area.
Alternative techniques for storing and retrieving files are disclosed in the Japanese laid open Patent No. 264379-1987 and No. 76560-1988.